am I completely lost by all this early round logistical business
There's 52 threesomes in a 156 player field. Tee times are about 12 minutes apart so you get 5 starts an hour, 10 if you use 2 "first holes" and Merion is using 1 and 11 for this. Then you have to factor in the guys making the turn running into guys just teeing off.
LOL. Much confusion understandable. :-D